To win a fight in WAR, you have to keep a couple statements true. First, your outgoing DPS must exceed your enemy's mitigation and healing. If this does not occur, you will never kill your opponent. Second, incoming DPS must be handled adequately by your mitigation and healing to allow your outgoing DPS enough time to score kills.
The ultimate resource in WAR, and life for that matter, is time. Having DPS and Support numbers to compare is useless unless you can convert this into time. Specifically, I'm referring to time to kill, or TTK. The two initial statements can be summarized with the following statement: Your TTK must be less than your enemy's TTK to win a fight.
TTK in WAR changes geometrically with the ratio of DPS to Support. Say for instance you are running around solo and you bump into a healer. For this example, say the healer won't attack you and will just heal himself to buy time for friends to show up. The healer is capable of healing himself for 700 hp/sec and you are capable of dealing 1200 hp/sec and the healer has 7500 health. Your DPS overcomes his healing at a rate of 500 hp/sec, meaning he will drop in 15 seconds. You get help from an ally, who can also deal 1200 hp/sec to this player. The healer is now taking 1700 hp/sec over his healing capacity, meaning he will drop in about 4.42 seconds instead. The DPS doubles while the TTK drops by a factor of about 3.4. Even a 25% increase in damage, 400 hp/sec more outgoing damage, would cut TTK in about half.
TTK is about how much DPS exceeds the available Support. I've been able to approximate TTK in small group encounters using the ratio of DPS to Support available at any given time. I determined this experimently through watching a lot of the raw scenario footage I have. Feel free to test it yourself.
Tarelther's Simplified Group Theory of TTK states that TTK is approximately equal to 10 seconds divided by the point difference of one group's DPS and the other's Support at any given moment. It assumes equal rank, gear and renown on each side. The formula can be modified to account for these differences, but that's another post. Also, this only gives a snapshot of any given moment. It changes constantly during the course of the battle.
The phrase at any given moment is important because the key to consistently winning even match-ups is to temporarily alter this ratio into your favor by various means.